Small arms caliber and/or power reducing adapter device

ABSTRACT

The present invention ( 2 ) is a small arms caliber and/or power reducing device for using a primer ( 18 ) to fire a projectile ( 21 ) and thence directionally guide the trajectory of said projectile from a firearm ( 1 ) the barrel bore of which may be substantially larger than the caliber of said projectile. 
     The present invention may be adapted by selecting appropriate external dimensions, internal dimensions and form factors to enable its use with any existing breech loading small arm chambered for center-fire cartridge ammunition. 
     The present invention may be constructed of two parts: 1) An adapter sleeve ( 10 ), and 2) a chamber ( 14 ), and intended to be re-loadable for multiple uses. Alternatively, the present invention may be configured as a single piece, fabricated with a primer and a projectile disposed therein, and intended to be used one time and discarded. 
     Suitable primers may include Standard Small Rifle or Small Pistol Primers, Standard Large Rifle or Large Pistol Primers, or Standard 209A Shotgun Primers. 
     Suitable projectiles may include Standard No. 3 Steel Shot, Standard .177 cal. B-B Air Gun Ammunition, or Standard .177, .20, .22 cal. or 6 mm Pellet or Plastic Air Gun Ammunition.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

FEDERALLY SPONSORED RESEARCH

Not Applicable

BACKGROUND OF THE INVENTION FIELD OF INVENTION

The present invention relates to firearm ammunition and more particularly to a small arms caliber and/or power reducing adapter device for firing, and directionally guiding the trajectory of, a projectile from a small arms piece wherein the caliber of said projectile may be substantially smaller than the barrel bore of said small arms piece.

It is known in the firearms art to convert a firearm of a particular barrel bore caliber to one having a smaller caliber. The motivations for this may be to permit safe, accurate, economical, reduced noise and reduced recoil education, target practice, or recreational shooting while using a substantially reduced backstop than that required for use of larger caliber or more powerful ammunition. The novel features of the structure of the present invention permit its safe, effective and instantaneous adaptation to various types of existing small arms such as pistols, semi-automatics, revolvers, rifles, shotguns and like firearms while requiring no modifications, alterations or additions to said existing small arms.

Inventions seeking these advantages have historically fallen into to classes: 1) Kits that include a barrel liner and 2) Those comprising a casing enabling use of cartridge ammunition in firearms of larger bore than those for which said ammunition was designed.

The class of inventions using a barrel liner is typified by U.S. Pat. No. 5,729.927 to Shaver, Jr. and U.S. Pat. No. 4,735.,009 to Jett, Jr. The present invention incorporates the guidance function of the barrel liner of this class of invention by use of a bore provided in the adapter device, thus wholly eliminating the need for a barrel liner. Elimination of said barrel liner greatly simplifies manufacture and use of the present invention while substantially reducing its manufacturing costs relative to kits requiring use of a barrel liner. Further, inadvertent discharge of large caliber, full power ammunition in a firearm in which a small caliber barrel liner is installed may result in destruction of said barrel liner, damage to or destruction of said firearm and/or injury or death to the shooter and/or bystanders. Elimination of said barrel liner completely eliminates the possibility of discharging a firearm with a barrel obstructing barrel liner installed on said firearm.

The class of inventions using cartridge casings is typified by U.S. Pat. No. 5,157,210 to Davis, U.S. Pat. No. 4,955,300 to Bertiller, et al., and U.S. Pat. No. 4,955,157 to Brighton, et al.

U.S. Pat. No. 5,157,210 exclusively adapts shotgun shells of a smaller gauge or bore to a shotgun of larger gauge. The cartridge adapter provides no directional guidance to the shot charge, this function being accomplished by the larger gauge barrel of said shotgun.

U.S. Pat. No. 4,955,157 utilizes an adapter shell as a component of a small caliber adapter kit intended to exclusively adapt a center-fire semi-automatic pistol to fire .22 caliber rim-fire ammunition. The adapter shell's primary purpose is to allow rim-fire ammunition to be fired by said pistol's centrally located firing mechanism. The barrel of the kit then directionally guides the trajectory of the .22 caliber projectile.

U.S. Pat. No. 4,955,300 utilizes an adaptive cartridge as a component of a sub-caliber barrel system. The primary purpose of the adaptive cartridge is to provide electrical ignition to the sub-caliber barrel system, thus reducing combustion residue and improving the reliability of said sub-caliber barrel system. The barrel of the system then directionally guides the trajectory of the sub-caliber projectile.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a small arms caliber and/or power reducing device for utilizing the explosive force of a primer to propel a projectile, and thence directionally guide the trajectory of said projectile, from a small arms piece the barrel bore of which small arms piece may be substantially larger than the caliber of said projectile comprising: an adapter sleeve and a chamber.

All embodiments of the present invention have an adapter sleeve that has external dimensions and shape chosen to replicate those of cartridge ammunition for a small arms piece and said adapter sleeve has a front end and a rear end, a channel running axially through said adapter sleeve forming a bore to directionally guide the trajectory of a projectile and said channel has a front end and a rear end, and may have a protective recessed crown at said front end of said channel.

A one piece embodiment of the present invention has a chamber at said rear end of said channel with a primer pocket with a front end and a rear end and a projectile pocket with a front and a rear end. The rear of said primer pocket opens to the rear end of the adapter sleeve and may have a beveled rim on said opening at said rear end and said front end of said primer pocket opens to and is axially aligned with said rear of said projectile pocket and said front of said projectile pocket opens to and is axially aligned with said rear of said channel.

A two piece embodiment of the present invention has a chamber pocket at said rear end of said adapter sleeve and said chamber pocket has a front end and a rear end and said front end of said chamber pocket opens to and is axially aligned with said rear end of said channel and said chamber pocket has internal dimensions that conform to external dimensions of a chamber that has a front end and a rear end and a primer pocket in said rear end and said primer pocket has a front end and a rear end and may have a beveled rim on the opening at said rear end of said primer pocket and said front end of said primer pocket opens to and is axially aligned with said rear of said projectile pocket and said chamber may be secured by mechanical, adhesive and/or other means in said chamber pocket in such a manner that said front end of said projectile pocket opens to and is axially aligned with said rear end of said channel.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring to the drawings which disclose one advantageous embodiment of the present invention and several modifications thereof:

FIG. 1 is a cross-sectional side elevational view of a shoulder mounted small arms piece disclosing an embodiment of the present invention disposed in the chamber thereof.

FIG. 2 is an exploded cross-sectional side view of a two piece embodiment of the present invention with a smooth-bore channel.

FIG. 3 is a cross-sectional side view of a two piece embodiment of the present invention with a smooth-bore channel.

FIG. 4 is a cross-sectional side view of a one piece embodiment of the present invention with a smooth-bore channel and disclosing a primer and spherical projectile disposed therein.

FIG. 5 is a cross-sectional side view of a two piece embodiment of the present invention with a rifled-bore channel and disclosing a primer and a cylindrical or otherwise configured projectile disposed therein.

LIST OF CALLOUTS

-   1. Small arms piece -   2. Present invention -   3. Firing mechanism of small arms piece -   4. Barrel bore of small arms piece -   5. Chamber of small arms piece -   6. Axis of adapter sleeve channel -   7. Axis of barrel bore of firearm -   8. Two piece embodiment of the present invention -   9. One piece embodiment of the present invention -   10. Adapter sleeve -   11. Adapter sleeve front end -   12. Adapter sleeve rear end -   13. Chamber pocket -   14. Chamber -   15. Chamber front end -   16. Chamber rear end -   17. Primer pocket -   18. Primer -   19. Beveled rim -   20. Projectile pocket -   21. Projectile -   22. Channel -   23. Recessed crown -   24. Smooth-bore channel -   25. Rifled-bore channel -   26. Firing mechanism protector -   27. Primer extractor -   28. Rod -   29. Enlarged end

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1 of the drawings, a small arms piece 1 is disclosed, including the firing mechanism 3, the barrel bore 4 and the axis of said barrel bore 7 of said small arms piece and the present invention 2 disposed in the chamber 5 of said small arms piece. It is to be understood that the present invention is not to be considered as limited to the specific firearm disclosed but the invention can be utilized with other types of known firearms such as pistols, revolvers, semi-automatics, rifles, shotguns and other firearms.

The present invention is a novel small arms caliber and/or power reducing adapter device for utilizing the explosive force of a primer 18 to propel a projectile 21 and thence directionally guide the trajectory of said projectile along the axis of the barrel bore 7 of said small arms with no need for said projectile to contact said bore of said small arms piece comprising: an adapter sleeve 10 and a chamber 14 which may be configured as a two piece embodiment FIG. 3 or one piece embodiment FIG. 4.

A two piece embodiment of the present invention may comprise: 1) an adapter sleeve intended for multiple uses formed of material selected to significantly resist repeated explosive and abrasive forces such as die cast or machined metal and with external dimensions and shape chosen to replicate those of loaded cartridge ammunition for a breech loading small arms piece and said adapter sleeve having a front end 11 and a rear end 12 and a chamber pocket 13 centered in said rear of said adapter sleeve which opens to and axially aligns with a channel 22 which may be smooth-bored 24 or rifled-bored 25 and which is smaller laterally than said chamber pocket and which extends along the axis of said adapter sleeve 6 from the front of said chamber pocket to said front of said adapter sleeve and may have at its front end a protective recessed crown 23 and 2) a chamber that has a front end and a rear end and with external dimensions selected to conform to the internal dimensions of said chamber pocket and with an opening at said rear of said chamber, and which may have a beveled rim 1 9 to facilitate insertion of said projectile and/or said primer, forming a primer pocket 17 and the front of said primer pocket opens to and axially aligns with an opening in said front of said chamber which forms a projectile pocket 20 the front which, when said chamber may be secured in said chamber pocket by mechanical, adhesive, and/or other means, opens to and axially aligns with the rear of said channel.

A one piece embodiment of the present invention may have said adapter sleeve and said chamber formed as one piece of a material less resistant to explosive and abrasive forces such as molded polymer and may incorporate all components of a two piece embodiment and also be fabricated with said primer and said projectile disposed therein and intended for a single use.

In these embodiments of the present invention, said chamber is formed of a material that is at once so resilient as to permit easy insertion of said projectile and said primer and thence securely retain said projectile and said primer and/or permit easy extraction of said primer and also so firm as to provide sufficient resistance to forward movement of said movement of said primer to ensure that said firing mechanism of said small arms piece reliably dents and thus detonates said primer.

Additionally, the present invention provides a firing mechanism protector 26 with external dimensions and shape chosen to replicate those of said primer and may be formed of a firmly resilient material such as a polymer which, when inserted into said primer pocket will permit dry firing of said small arms piece and prevent damage to or breakage of said firing mechanism of said small arms piece.

Further, the present invention may be supplied with a primer extractor for removing a fired primer, an unfired projectile and primer or said firing mechanism protector from said chamber comprising: a rod 28 with external dimensions and shape chosen to permit its insertion into said front of said channel and through said projectile pocket and said primer pocket thus expelling said primer and/or said projectile or said firing mechanism protector and one enlarged end 29 to facilitate application of manual pressure to said primer and/or said projectile or said firing mechanism protector.

Operation of a two piece embodiment of the present invention may be accomplished by placing a primer on a firm horizontal surface with its front or open end up and placing a projectile thereon and manually pushing said rear end of said adapter sleeve down onto said projectile and said primer so that said projectile passes through said primer pocket and is disposed in said projectile pocket and said primer is subsequently disposed in said primer pocket, this procedure being facilitated by said beveled rim of said primer pocket. Said adapter sleeve may then be disposed into a chamber of said small arms piece. Said small arms piece may then be discharged in the usual manner whereupon said firing mechanism detonates said primer the explosive force of which propels said projectile through said channel of said adapter sleeve which thus directionally guides said projectile along said axis of said barrel bore of said small arms piece and thence towards a desired target.

Upon discharge of said projectile, said adapter sleeve may be extracted or ejected from said chamber of said small arms piece. Said primer may be extracted from said primer pocket by manually inserting said rod of said primer extractor through said channel and applying manual pressure to said enlarged end and thus via said rod to the front of said primer thus expelling said primer from said primer pocket. The above described loading, firing and extracting procedures may be repeated multiple times.

Operation of a two piece embodiment of the present invention utilizing said firing mechanism protector is accomplished by disposing said firing mechanism protector in said primer pocket by a procedure identical to that of loading said projectile and said primer. Said adapter sleeve may then be disposed in a chamber of said small arms piece. Upon dry firing said small arms piece said firing mechanism protector provides rearward resistance to forward movement of said firing mechanism thus preventing damage to or breakage of said firing mechanism in a manner identical to that of a standard snap-cap or dummy round. Said firing mechanism protector may be extracted from said primer pocket in a procedure identical to that of extracting fired said primer.

Operation of the one piece embodiment of the present invention wherein said invention is fabricated with said projectile and said primer disposed therein may be accomplished by disposing said adapter sleeve into said chamber of said small arms piece and thence discharging said small arms piece in the usual manner. Said adapter sleeve may then be extracted or ejected from said chamber of said small arms piece and thence discarded.

PRIMER AND PROJECTILE COMBINATIONS MAY INCLUDE, BUT ARE NOT LIMITED TO: PRIMER PROJECTILE Standard Small Rifle or Standard No. 3 Steel Shot Small Pistol Primer Standard Large Rifle or Standard .177 cal. B—B or Large Pistol Primer Pellet Air Gun Ammunition Standard 209 Standard .177, .20, .22 cal. or Shotgun Primer 6 mm Air Gun Ammunition

Accordingly, the reader will readily see that the novel adapter device of the present invention is straightforward and economical in design, construction, manufacture, and operation. It provides several desirable advantages that advance and enhance the adaptation of small arms to a reduced caliber for safe, accurate and economical firearm safety and proficiency education, target or practice shooting, and recreational shooting:

-   -   Efficiency of manufacture using economical and readily available         materials and relatively simple and well-understood procedures;     -   Immediate adaptability to any firearm of a particular caliber or         gauge, regardless of barrel length;     -   Enhanced safety by forgoing use of a barrel liner, thus         eliminating the possibility of discharging full size and power         ammunition in a firearm with a sub-caliber barrel liner         installed thereon;     -   Economy and simplicity of operation due to ease of reloading         utilizing economical and readily available standard primers and         projectiles;     -   Convenience of operation when configured as one piece and         fabricated with primer and projectile in place to be used once         and discarded.

The above descriptions should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. For example, the channel may have hexagonal rifling rather than grooved rifling, etc.; the chamber may be configured to hold sub-caliber cartridge or non-cartridge ammunition, etc.; the channel may be shortened to comprise only the projectile pocket when the device is to be used in a firearm with a barrel bore no larger in diameter than the caliber of a projectile, etc.

Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. 

1. A device for utilizing the explosive force of a primer means for firing a projectile means from a breech loading small arms piece said small arms piece chambered for cartridge ammunition, said device comprising: a. An adapter sleeve with form factors and external dimensions and shape chosen for disposing into a firing chamber of said small arms piece and b. a chamber with form factors and internal dimensions and shape chosen for securing said primer means and said projectile means within said adapter sleeve and, when said adapter sleeve is disposed in said firing chamber of said small arms piece, said chamber opens to and axially aligns with a firing mechanism and a barrel bore of said small arms piece for axially aligning said primer means with said firing mechanism of said small arms piece and axially aligning said projectile means with said barrel bore of said small arms piece.
 2. The device of claim 1 with a channel that extends axially through said adapter sleeve and that opens to and axially aligns with said chamber and, when said adapter sleeve is disposed in said firing chamber of said small arms piece, opens to and axially aligns with said barrel bore of said small arms piece for directing the trajectory of said projectile means.
 3. The device of claim 2 wherein said channel is smooth bored.
 4. The device of claim 2 wherein said channel is rifled or otherwise axially configured for imparting axial rotation to said projectile means.
 5. The device of claim 2 wherein said chamber has form factors and internal dimensions and shape chosen for securing cartridge ammunition of smaller caliber and/or less power than that of standard cartridge ammunition of said small arms piece and said channel may have form factors and internal dimensions and shape chosen for imparting axial rotation to and/or directing the trajectory of a projectile means of said ammunition of said smaller caliber and/or reduced power.
 6. A firing mechanism protector with form factors and external dimensions and shape chosen for disposing into said chamber of said device or into a primer pocket of a cartridge case and providing resilient resistance to movement of said firing mechanism of said small arms piece. 